Philadelphia ranks as the 10th most polluted city in the nation for soot, or fine particulate matter, which is an air pollutant known to cause respiratory illness, heart attacks and even premature death, according to the American Lung Association.

“On hot, humid days like today we are especially at risk from air pollution like soot, which poses a serious threat to our children and people with asthma like my young nephew. I’ve watched him deal with the challenges of not being able to breathe well first-hand. We’re here today to show our support for stronger limits on soot pollution that will clean up our air and mean healthier families in Philadelphia,” said Jackie Wilson, a volunteer with the Philadelphia Sierra Club.

Exposure to soot can cause heart attacks, strokes, worsened asthma, lung inflammation, cancer, developmental and reproductive harm and even premature death, according to the EPA. Those most at risk include children, the elderly, those suffering from respiratory or heart disease, diabetics, low-income communities and people who work, play or exercise outdoors. Coal-fired power plants are one of the leading sources of soot pollution along with petroleum refineries and diesel exhaust.

“Soot is so small that its very nature makes it one of the most dangerous forms of air pollution. It is easily inhaled, where it can then enter the bloodstream and contribute to heart attacks, strokes and asthma attacks. Young children, like mine, are especially susceptible to soot as they breathe more rapidly and inhale more dangerous particulate matter,” said Gretchen Alfonso, a mother of two from Pennsport, who represents the Mom’s Clean Air Force in Philadelphia.

Supporters of the new, stronger EPA limits held a rally with a mom’s stroller brigade that marched from the hearing to Independence Mall to show support from moms and parents who are worried about their children’s health.

“For my daughter who suffers from Philadelphia’s poor air quality, my son who loves, and at three, needs to play outside, my husband who rides his bike to work, and for myself and every other Pennsylvania mom who tries her best to put the health of her family first, I applaud the Environmental Protection Agency for finally stepping up for the health of our children and strengthening the limits on soot pollution,” said Alfonso in her testimony to the EPA.

A broad coalition of groups turned out to support the new limits, including the Clean Air Council, Citizen’s for Pennsylvania’s Future (PennFuture), Pennsylvania Conservation Voters, PennEnvironment, Sierra Club, Interfaith Power and Light, Mom’s Clean Air Force, Natural Resources Defense Council, National Wildlife Federation and more.